Conventional ratchetable open-ended wrenches, such as U.S. Pat. No. 1,320,668, U.S. Pat. No. 7,111,529, and US Patent Application No. 20100083797, respectively mainly comprises: a wrench body and a retractable jaw member; the wrench body comprising head with two opposite jaws and a receiving hole between the two jaws; the retractable jaw member being slidably mounted on the head, the first side being directing to the receiving hole and having engaging portion; the retractable jaw member and the head being against with an elastic member; the retractable jaw member being able to move from a first position to a second position in the sunken slot, and being able to limit a workpiece rotating in the receiving hole when at the first position and allowing the workpiece to rotate in the receiving hole when at the second position.
However, the aforementioned prior arts have the following disadvantages: (a) the elastic member of the U.S. Pat. No. 1,320,668 is mounted in a cave transversely provided on the lateral side of the head; the cave is hard to be manufactured, and is exposed outside so as to decrease the pleasing to the eyes; moreover, the retractable jaw member only has one engaging surface, so that the retractable jaw member is very easy to be moved when in driving status so as to decrease the driving force; (b) the elastic member of the U.S. Pat. No. 7,111,529 is mounted in a penetrating gap provided on one jaw so as to decrease the strength of the jaw; moreover, the retractable jaw member only has one engaging surface, so that the retractable jaw member is very easy to be moved when in driving status so as to decrease the driving force; (c) the retractable jaw member of the US Patent Application No. 20100083797 only has two engaging surfaces, so that the retractable jaw member is very easy to be moved when in driving status so as to decrease the driving force; moreover, the width of the retractable jaw member is not enough, and the slot for receiving the spring is provided on the engaging portion which mainly stand the driving force, so that the strength of the retractable jaw member is decreased, and the retractable jaw member is very easy to be damaged.